Film treating apparatus



Jan. 3, 1939.v A w, TONDREAU 2,1421538v FILM TREATING APPARATUSFiled-ocr, :28,` 193e 2 sheets-Shadi Jan. 3, 1939. A: W, TONDREA-g2,142,538

FILM TREATING APPARATUS Filed` oct. 28, 193e 2 sheets-sheet 2 ATTORNEYPatented Jan. 3, 1939 UNITEDY STATES PATENT OFFICE FILM TREATIN GAPPARATUS Application October 28, 1936, Serial No. 108,029

2 Claims.

This invention relates to film treating apparatus and has particularreference to apparatus for cleaning photographic film.

During the printing, projection, and handling ci motion picture film,the film has a tendency tc accumulate dirt, oil, lint, etc., on thesurface thereof, which not only prevents a clear reproduction of theimages or sound track on the lm, but also tends to cause deteriorationof the nlm as well.

One object of the present invention is to clean the surfaces of a motionpicture lm.

Another object of the invention is to permit passing the lm at arelatively high speed through a cleaning apparatus without injury to thesurface thereof.

The invention utilizes a loop frame adapted to guide a motion picture lmthrough a suitable film cleaning liquid, in a series of folds or loops;preferably the emulsion surfaces of the lm being adjacent each other incertain ones of the loops and the uncoated surfaces of the film beingadjacent each other in certain others of the loops. Rctatable nlmcleaning members are provided within the various folds or loops and areadapted to be driven at a peripheral speed different from that of thei'llrn, thus causing a rubbing' and cleaning action on the surface ofthe iilm.

In order to permit a relatively high speed of the film through theapparatus without excessive rubbing action of the film cleaning membersduring their engagement with the surface of the nlm, these cleaningmembers are preferably rotated in the same direction as the lm and at aspeed such that the relative velocity between the periphery thereof andthe film is sufficient to thoroughly clean the film without damaging thesurface thereof due to too high a relative rubbing velocity.

More particularly describing the invention, reference is had to theaccompanying drawings, wherein:

Fig. l is a sectional elevational view of a lilm cleaning apparatusembodying the present invention.

Fig. 2 is a transverse sectional View of the nlm cleaning apparatus andis taken along the lines 2 2 of Fig. 1.

Fig. 3 is a front view of one of the lm cleaning drums.

Fig. 4 is a transverse sectional view through a drum and is taken alongthe line 4-4 of Fig. 3.

Fig. 5 is a fragmentary sectional plan view of the film cleaning tankand lower spool head, and is taken along the line 5-5 of Fig. 1.

Referring now to Figs. 1 and 2, the film cleaning apparatus comprises arectangular tank it, adapted to contain a film cleaning liquid, such ascarbon-tetrachloride. Tank IIJ is supported at its upper and open end bymeans of a deck i l, win'ch in turn is supported by standards I2 and It.A loop frame generally indicated at la is provided within the tank It toguide a motion picture film (negative or positive) to be cleaned. in aseries of folds or loops as at I5, I6, Il and I8 through the lm cleaningliquid. Frame le comprises a pair of vertically extending guide bars i5and E9 secured to a horizontally extending supporting bar 26. Bar 2U isremovably supported on either end thereof by means of a pair of brackets2| and 22, secured to deck Si. As shown in Fig. 5, each of the guidebars i9 and le is slidably secured within tank lil by means of a pair ofvertically extending angle members 23 and 2li, suitably secured to theend walls and 29 of the tank I@ in slidable engagement with each side ofthe respective guide bars. This construction permits the entire loopframe I to be removed from the tank Ii) by removing screws 26 onbrackets 2i and 22 and thence raising the frame I 4 upwardly and out ofthe tank it.

An upper spool head 21, having a series oi spaced, laterally aligned, lmguiding spools 28 freely rotatable thereon, is rigidly secured betweenthe vertical guide bars I9 and IS.' Spool head 2l is preferably keptwithin the cleaning liquid, the upper level of which is indicated by thedotted lines L of Fig. 1. A lower spool head Sii, also having rotatablefilm spools 3l in late-f alignment with each other, is provided belowthe upper spool head 22'. Brackets 32 and cn either end of head 30 carryat their upper and lower ends flanged guide wheels 34 and 35,spectively. These guide wheels ride along the inner surfaces of thevertically extending guide bars I9 and I9 to permit the spool head 3S tobe adjustably supported within the tank it in lateral alignment with theupper spool head 2?. Stop members 36 provided on each of the brackets 32and 33 are adapted to engage outwardly extending pins 3'! on therespective adjacent guide bars I9 and I9' when frame I4 is being raisedor when the nlm being cleaned breaks, thus effecting the removal of thelower speel head 3!! with the rest of frame I4 when desired forcleaning, repair or threading purposes.

A series of film cleaning drums 33, 4Q, il and d2 provided withincertain of the lm folds, as at I5, IS, I1 and I 8, respectively, aresecured to shafts (Fig2) journaled in bearings 43 which i are suitablysecured to a horizontally extending bar or head 44, provided between thevertical bars I3 and I9` Each of drums 39 to 42, inclusive, ismaintained below the surface of the cleaning liquid.

With reference to Fig. 1 it will be noted that one surface of the film,for'example the uncoated surface, will be adjacent itself in the loopsI5 and I5 while the opposite surface or emulsion coated surface, will beadjacent itself in successive loops I1 and I8, thus insuring cleaning ofboth surfaces of the film by the respective drums 39 to 42, inclusive.Each of the various film cleaning drums 39 to 42, inclusive, is rotatedin the direction of the lm engaged thereby. For example, drums 39 and4l) are rotated in a clockwise direction to engage the respective foldsI5 and I6 of the film traveling in the direction indicated by the arrowsA and B, while the drums 4I and 42 are rotated in a counter-clockwisedirection to engage the film traveling in the direction indicated by thearrows C and D.

A drive shaft 52, extending longitudinally of the cleaning apparatus isprovided to impart rotation to the drums 39 to 42, inclusive, throughthe use of chains 41. Referring to Fig. 2 each of the various chains 41engages at the lower end thereof a chain sprocket 46 secured to the rearend of the shaft 45 of the respective film cleaning drum.

The upper ends of chains 41 are engaged by chain sprockets 48 rotatablyjournaled on stud members 50 extending from the upper supporting bar 29.Spiral gears 49 are integrally formed with those two of the sprockets 48which transmit rotation to the drums 39 and 4U, and are adapted to beengaged by similar spiral gears 5I secured on the drive shaft 52. 'I'hepitch of the teeth of each of the mating pairs of gears 49 and 5I, andthe rotation of the shaft 52, is such as to cause rotation of the drums39 and 49 in a clockwise direction as hereinbefore stated. The remainingchain sprockets 43 for transmitting rotation to the drums 4I and 42 arealso driven by the shaft 52 through the use of mating spiral gears II4and II5, similar to those of 49 and 5I, but with the teeth thereofinclined at an opposite angle to the teeth of gears 49 and 5I to causerotation of the drums 4I and 42 in a counterclockwise direction.

Drive shaft 52 is journalled within bearings 53, 54, and 55, and has adriving pulley 56 secured to one end thereof. A motor 51 supported belowthe deck I I drives the pulley 56 through a belt 58. Casings 9U, 9I, 92and 93 are provided to enclose the driving chains and other rotatingparts for driving the respective cleaning drums 39 to 42, inclusive.

A supply reel 60, adapted to support a roll of film to be cleaned, isrotatably supported on a bracket 6I carried at the upper left hand endof the deck I l. Film from reel 66 is guided under a freely rotatablefilm spool 62 secured to the bar 20, thence under a supply sprocket 63,also rotatably secured to bar 20. From sprocket 63, the film is guidedover the various spools on the upper and lower spool heads 21 and 3D,respectively, in a series of loops. The film on leaving the tank I0passes over a take-up sprocket 64 rotatably mounted on bar 20, under afreely rotatable film guiding spool 65, under a second film guidingspool 66 and thence onto a take-up reel 61. Sprockets 63 and S4 aredriven by drive shaft 52 through sets of mating spiral gears 13 and 14,respectively. The pitch of the teeth on the gear sets 13 and 14 is insuch an angular direction as to cause the sprockets 63 and 64 to propelthe film from left to right through the tank I0. Take-up reel 61 is alsodriven by motor 51 through the medium of a belt 68. Belt 68 passesaround a driving pulley 69, driven by motor 51, around an idler roller10, and thence around a driven pulley 1I suitably secured to the take-upreel 61. Preferably, a friction clutch (not shown) is provided betweenthe reel 61 and pulley 1I to permit compensation for the change inrotational speed of reel 61 due to the changing diameter of the filmroll thereon. A housing 12, having a door at one side thereof (notshown) to permit access to reel 61 and a slot 12' therein t0 permitentrance of the film into housing 12, is provided over the take-up reel61 and guide roller 66 to shield the cleaned film from dust and vaporemerging from the cleaning liquid.

A certain desired ratio between the speed of the film and the peripheralspeed of the cleaning drums is maintained by correctly proportioning thediameters of the film sprockets 63, 64, and the drums 39 to 42,inclusive, or by correctly proportioning the various driving gears andchain sprockets in an obvious manner. Thus any particular relative speedbetween the cleaning drums and the film may be maintained regardless ofthe speed of the film through the cleaning apparatus. However, in thepresent case the film is normally fed through the cleaning solution at avelocity of about feet per minute and the speed of the drums 39 to 42,inclusive, is such as to maintain a velocity of about 40 feet per minuteat the periphery thereof. Preferably a rheostat (notL shown) is insertedin the circuit of motor 51 to vary the speed of the film through thecleaning solution as desired.

A weight 82 is provided on lower spool head 30 to apply a suitablefriction between the surface of the film and the surface of the cleaningdrums. By replacing weight 82 with that of a greater or less weight, theforce of friction between the surface of the film and the periphery ofthe film cleaning drums 39 to 42, inclusive, may be changed as desired.This force of friction between the iilm and each or any of the filmcleaning drums may also be varied by changing the diameters of thedesired cleaning drums thus changing the angle of the film pathsthereover which, in turn, changes the horizontal component of forceintroduced by the weight 82.

The lrn on emerging from the cleaning solution is dried by means of airblasts from nozzles 84, 85, 86 and 81. through a conduit 88 from asuitable source of supply, such as a compressor (not shown). Nozzles 84and 85, provided on either side of the path of the film, are directeddownwardly against the surfaces of the film so as to blow a majorportion of the cleaning solution remaining on the surfaces of the film,back into the tank I5. These air nozzles 84 and 85 are fed directly bythe conduit 89. The other nozzles 86 and 81, situated adjacent the reelhousing 12, are directed against either side of the film and aresupplied with warmed air passing through an air heater 89 from theconduit 88. The warm air from nozzles 86 and 81 serves to evaporate anycleaning' solution remaining on the surfaces of the film before passingonto the take-up reel 61.

An automatic motor operating switch 'I5 is provided in conjunction withthe supply reel 60 to open the circuit of motor 51 when the film isnearly unwound from the supply reel 60. This Air is fed under pressureu.

.hub 95 by screws |05 and |06.

switching arrangement comprises a roller 16 carried by an arm 11,pivoted at 11', which is secured by a suitable link arrangement 18 to aswitch 19 connected in the circuit of motor 51. When the diameter of thefilm roll on reel decreases below a certain limit the arm 11 becorneseifective to operate the switch 19, and thus open the motor circuitbefore the end of the. film leaves the reel 60 and passes into the tankl0. A second supply reel is rotatably supported on bracket 6| above thesupply reel 60 and is adapted to contain thereon a roll of leader film8| which may be spliced or otherwise secured to the end of the film tobe cleaned, thus maintaining the apparatus in threaded position at alltimes and obviating the necessity of re-threading the apparatus for eachnew reel'of iilm to be cleaned.

The construction of the lm cleaning drums 39 to 42, inclusive, will beunderstood with reference to Figs. 3 and 4, wherein each of the drumscomprises an annular hub having an inwardly and centrally located web9B. A central hub 91 is formed in the center of web 96 to carry the drumupon a drive shaft. Annular hub 95 has a transversely extending slot oropening 98 therein which communicates with an enlarged opening 99 in theweb 96. An eccentric tensioning member |00 is provided within opening 99and has bearing portions |0| and |02 at either end thereof journaled inbearing blocks |03 and |04. Blocks |03 and |04 are secured on either endof annular Screw driver slots |01 are provided on either end ofeccentric |00 to permit rotatable adjustment of the eccentric. Acontinuous band of lm cleaning material |08 such as chamois, velvet,annel, etc., is wrapped around the periphery of hub 95 with a loopedportion |09 extending within slot 98 and around the eccentric portion ofeccentric |00. Rotation of the eccentric |00 in a clockwise directionfrom the position shown in Fig. 3 draws the band |08 tightly upon thehub 95. In order to lock the eccentric in any desired angular positionthe bearing portion |0I of eccentric |00 is extended and serrated as atH0. A locking member is pivotally mounted on the screw |06 and has aserrated portion ||2 adapted to engage and lock the serrated portion ofbearing |0|.

I claim:

1. An apparatus for cleaning film having an emulsion coated surface andan uncoated surface thereon comprising a tank adapted to contain a filmtreating solution, upper and lower spool heads adapted to guide saidfilm through said solution in a plurality of loops, means whereby saidlower spool head is adapted to be carried by the lm in said loops, thecoated surface of the iilrn being in opposed adjacent relation in atleast one of sai-d loops, a drum located in said loop, the uncoatedsurface of the film being in opposed adjacent relation in at least oneof said loops, a second drum located in said last mentioned loop, a filmcleaning material o-n the peripheries of said drums, each of said drumsbeing adapted to engage the adjacent surfaces of the lm in the foldwherein the drum is located, means adapted to move said lm through saidsolution and means for rotating said drums at a peripheral speed slowerthan the speed of said Iilm and in the same direction as said i'llm.

2. A iilm treating apparatus comprising a tank, upper and lower spoolheads in said tank, a lm treating element having a film treating surfacethereon, means for rotatably supporting sai-d element intermediate saidupper and lower spool heads, means for traversing a lm over said spoolheads in a loop, the treating surface. of said element lying in the pathof said loop, means whereby said lower spool head is adapted to becarried by the film in said loop to create frictional contact betweensaid film and the treating surface of said element, and means fordriving said element at a peripheral speed slower than the peripheralspeed of said traversing means to create a drag on said lm.

ALBERT W. TONDREAU.

